418 DISEASES OF CATTLE. 



little resistance to heat and drying. It has long been known that the 

 anthrax virus thrives best under certain conditions of the soil and on 

 territories subject to floods and inundations. The particular kinds of 

 soil upon which the disease is observed are black, loose, warm, humus 

 soils, also those containing lime, marl, and clay, finally peaty, .swampy 

 soils resting upon strata which hold the water, or, in other words, are 

 impervious. Hence fields containing stagnant pools may be the source 

 of infection. The infection may be limited to certain farms, or even to 

 restricted areas on such farms. Even in the Alps, over 3.000 feet above 

 sea level, where such conditions prevail in secluded valleys anthrax per- 

 sists among herds. 



Aside from these limitations to specific conditions of the soil, anthrax 

 is a disease of world-wide distribution. It exists in most countries of 

 Europe, in Asia, Africa, Australia, and in our own country in the Lower 

 Mississippi Yalley and perhaps elsewhere. 



Meteorological conditions have also an important share in determin- 

 ing the severity of the disease. On those tracts subject to inundations 

 in spring, a very hot, dry summer is apt to cause a severe outbreak. 

 The relation which the bacillus bear;s to these conditions is not posi- 

 tive!}" known. It may be that during and immediately after inunda- 

 tions or in stagnant water the bacilli find enough nourishment in the 

 water hero and there to multiply and produce an abundant crop of 

 spores, which are subsequently carried, in a dry condition, by the winds 

 during the period of drought and disseminated over the vegetation. 

 Animals feeding upon this vegetation may contract the disease if the 

 spores germinate in the body. 



Another source of the virus, and one regarded by many authorities as 

 perhaps the most important, are the bodies of animals which have died 

 of anthrax. It will be remembered that in such bodies the anthrax 

 bacilli are present in enormous numbers, and wherever blood or other 

 body fluids are exposed to the air on the surface of the carcass there 

 the formation of spores will go on in the warm season of the year with 

 great rapidity. It will thus be readily understood how this disease may 

 become stationary in a given locality and appear year after year and 

 even grow in severity if the carcasses of animals which have succumbed 

 to it are not properly disposed of. These should be buried deeply, so 

 that spore formation may be prevented and no animal have access to 

 them. By exercising this precaution the disease will not be dissemi- 

 nated by flies and other insect pests. 



We have thus two agents at work in maintaining the disease in any 

 locality, the soil and meteorological conditions and the carcasses of 

 animals that have died of the disease. Besides these dangers, which are 

 of immediate consequence to cattle on pastures, the virus may be car- 

 ried from place to place in hides, and it may be stored in the hay or 

 other fodder from the infected fields and cause an outbreak among 

 stabled animals feeding upon it in winter. 



